AJS & Matchless Owners Club

clive wrote:

SPRIDDLER wrote:

1608 wrote:
I would suggest first contacting the 'restorer' for specific info on what he had done, if anything, to the engine. The 'full restoration' may have just been cosmetics and an oil change............

Now now Sprids we are not all as generous with our stretching of the truth. I mean an oil change is that really necessary during a restoration?

No truth stretching Clive. The oil doesn't have to be new; merely changed.

Cynic? Moi?

1608 wrote:As all the above and especially as Nev has added, take now't for granted. How thorough was the rebuild! I would be inclined to check the sludge trap. I know it means a rebuild, but if it was done properly then there will be the minimum of parts expense and great peace of mind.

Just out of interest, is the sludge trap also known as something else? I can't find any reference to it in the workshop manual. At what sort of mileage should it be checked and cleaned, or would it simply be left until something needed fixing in the bottom end?

I got my twin running last April and have been running it quite happily (usually!) since then. It didn't even occur to me to strip the bottom end, since everything down there sounded fine, oil is circulating etc.

Malc

Hi

Manufactured into the crank shaft - see here:

http://www.jampot.com/forum/viewtopic.p ... ion#p69261

Regards Mick

Hi Mick

Thanks, that's interesting. Based on that topic it seems that I may not have a sludge trap as such, being a 1960 machine. As I said, I could see no reference to cleaning anything out in the workshop manual.

Cheers,

Malc

MalcW wrote:Hi Mick

Thanks, that's interesting. Based on that topic it seems that I may not have a sludge trap as such, being a 1960 machine. As I said, I could see no reference to cleaning anything out in the workshop manual.

Cheers,

Malc

If it's a twin you'll definitely have sludge traps in the crank 100%.

Curses! That's something else I'll have to worry about now, every time I go for a ride! Stressful, this classic bike riding...

Malc

MalcW wrote:Curses! That's something else I'll have to worry about now, every time I go for a ride! Stressful, this classic bike riding...

Malc

Surely the trap would takes a fair old while to plug up? - especially with modern oils. In any event, would not the oil would simply bypass it - albeit contaminated. I seriously doubt whether starvation to the big ends would occur. By all means unplug them when doing the bottom end, but meanwhile, changing the oil regularly is the surely the best means of preventing further contamination. If really concerned, I guess you could fit an in-line filter.

It does take a while to fill the traps if they've been cleaned out before assembly. However if after regrinds etc they aren't cleaned out then it doesn't take long for things to go pear-shaped. I've had many through my hands that I've had to actually drill out as they'd never been done for years, even after regrinds by the state of some of them.

However if a motor has been running for a while without any issues arising then an oil change regularly should keep things tip top.

Pear-shaped? How? I don't see any failure of big ends or main bearing occurring as the oil will just bypass. Granted it would be foolish to ignore the problem of plugged up slugde traps indefinitely, but with regular oil changes and modern single grade oils the risk of such failures - even with a plugged up trap - is IMHO minimal.